Field of the Invention
The present invention relates to a color conversion technique used in an image processing apparatus.
Description of the Related Art
Recently, the technique of creating a printed matter having an elevation has been widely spread and the demands for color matching thereof have increased. In such a printed matter, it is known that the color gamut enlarges or reduces depending on a print layer stacking method or a roughness (for example, color material density improves and the color gamut enlarges as more print layers are stacked). Here, a user confirms a printed matter which is created based on input color data and determines whether a desired color gamut is obtained or not, and, in the case that the color gamut is not sufficiently wide, the user may obtain the desired color gamut by stacking print layers. In such a case, it is necessary to confirm whether the desired color gamut is obtained or not in the print result, by the measurement of the printed matter or user's visual observation. Further, in the case that the desired color gamut is not obtained, it is necessary to perform the printing again after the change of color parameters and to repeat the above confirmation operation, resulting in an increase of workload.
Japanese Patent Laid-Open No. 2013-14057 proposes a method of presenting a user with a color gamut target for each print layer stacking in the case that the print layer is stacked in a substantially flat surface state for confirming whether a desired color gamut is obtained or not. In Japanese Patent Laid-Open No. 2013-14057, ink amount is determined from input color data for the printing of each print layer by the use of a profile which defines a corresponding relationship between the input color data and the ink amount to be used in each print layer. This profile defines the ink amount so as to enlarge the color gamut every time each print layer is stacked to be printed, and therefore the user can confirm a relationship between the number of print layers and the color gamut easily from the number of stacked print layers without trial and error.
While the technique of enabling the color prediction on a substantially flat surface has been proposed as described above, simple color prediction cannot be performed for a rough surface having a roughness as used in a elevation printing because the roughness is different in each pixel. The technique of Japanese Patent Laid-Open No. 2013-14057 assumes that the print layer is stacked on a substantially flat surface, and therefore cannot present the user with a color gamut target on a rough surface having a roughness. For the confirmation of a print color corresponding to the color gamut change on such a rough surface having a roughness, it could be effective to hold information showing a color gamut for each rough surface having roughness. Then, it could be effective to confirm the print color of a rough surface utilizing input information indicating the rough surface having a roughness and the held information of the color gamut. In the case like this, it is inevitable to hold profiles corresponding to information of all the rough surfaces having roughness and there arises a problem that memory cost is increased and a large amount of printing and measurement for profile generation should be performed.